Bend-insensitive, single-mode sensor grade fibers, available with 820, 1310, and 1550 nm cutoff wavelengths, feature a high NA of 0. 16, making them suitable for tightly wound fiber spools for a variety of sensing applications. When stressed by bending, light in the outer part of the core is no longer guided in the core of the fiber so some is lost, coupled from the core into the cladding, creating a higher loss in the stressed section of the fiber. If you put a. Bend-insensitive single mode fibres (ITU-T G. A2) are a crucial part of the world's shift towards flexible and reliable connectivity. This article, with the loss of optical fiber, mainly describes the current popular structure design of bend-insensitive fiber and the influence of bending on the mechanical strength of fiber and introduces some ap es may lead to the fiber should not be. Written by Ben Hamlitsch, trueCABLE Technical and Product Innovation Manager RCDD, FOI One of the important considerations when looking at optical fiber for installation is bending concerns. This is because fiber optic cable is sensitive to stress, particularly bending. F-SBC Optical Fiber, Singlemode, 1310/1550 nm, Bend Insensitive.